In my experience, the 40-man roster is completely accurate, but to save time, if a player is not on his club's 40-man roster, he will not be put in the game. All players not on the 40-man roster do not exist.
Are you sure that's the name of the guy? The only thing that comes up for Adam Erickson is a NCAA Football player that plays for the Georgia Dogs.
According to baseball-reference.com, no player named Adam Erickson has ever played professional-level baseball. And considering they are "very" thorough for recent years and include every level of minor league baseball, this Erickson is fake.
Did you simulate? Might have generated a new person.
In mlb 2k13 there are some players that are real good in the game but I'm not sure theyre real, Adam Erickson is one on Lehigh Valley / Reading
